King Henri IV himself ordered Marthe Brossier’s exorcism. He had some of the highest priests in the country gather around her, sprinkling her with holy water and reciting scriptures in Latin while the demon in Brossier, tormented by the Holy Scriptures, screamed in agony and pain.

But what Brossier didn’t know was that her exorcism was a sham. The holy water was just ordinary water, and the Latin books the priests were reading were nothing more than an old poem by Virgil.

Her exorcism was a science experiment – the first time in history that a demonic possession was systematically put to the test . Brossier failed – and in the process, revealed some incredible things about the human mind.

[Read the full article at Ancient Origins.]